Hello: Code is pretty specific on this, the line from the relief valve needs to drain so water isn’t trapped in it. There cannot be more than four 90 degree bends and it must stay full size (3/4″). Rheem is different than other manufacturers in that it’s ports can be deeper and restrict flow from a normal combo anode.
So, you do have choices, but the best fix is to get the drain line right. Another meddlesome thought I just had is to raise up the heater if you have room for it 🙂